TWI709953B - Pixel array - Google Patents

Abstract

A pixel array comprising a plurality of display units. The display units respectively include a plurality of light emitting elements, a plurality of scan switches, a data switch, and a plurality of light emitting switches. The light emitting elements are connected in series and have a first end and a second end, respectively. The scan switches are respectively coupled the first end of the corresponding light emitting element. The data switch receives a data voltage to provide a data current according to the data voltage. The light emitting switches are respectively coupled between the second end of the corresponding light-emitting element and the driving switch for receiving the data current. The turned-on scan switch and the turned-on light switch determine the amount of illumination in the light-emitting elements.

Description

Pixel array

The present invention relates to a pixel array, and more particularly to a self-luminous pixel array.

In the existing active self-luminous pixel array, the current value (that is, the pixel current) flowing through the light-emitting element is controlled by a transistor, and in order for the conduction degree of the transistor to meet the required gray scale (that is, Brightness), each gray scale needs to be able to effectively adjust the current. However, due to the specifications of the source IC, there is a minimum limit on the difference between each gray scale voltage. Moreover, when the pixel current passes through the transistor to the light-emitting element to convert the light-emitting brightness, the voltage between the source and drain of the transistor will be much greater than the forward conduction voltage of the light-emitting element, so that most of the power consumption falls on the electrical On the crystal, the power consumption is wasted, so a novel pixel circuit is needed to improve the power consumption of the circuit.

The invention provides a pixel array, which can improve the overall display brightness.

The pixel array of the present invention includes a plurality of display units. The display unit includes multiple light-emitting elements, multiple scan switches, data switches, and multiple light-emitting switches. turn off. The light-emitting elements are connected in series and each have a first end and a second end. The scan switches are respectively coupled to the first ends of the corresponding light-emitting elements. The data switch receives the data voltage to provide the data current according to the data voltage. The light-emitting switches are respectively coupled between the second end of the corresponding light-emitting element and the driving switch for receiving data current. The turned-on scan switch and the turned-on light-emitting switch determine the amount of light emitted in the light-emitting element.

Based on the foregoing, the pixel array of the embodiment of the present invention utilizes the concept of series connection of light-emitting elements, so that the data current can flow through multiple light-emitting elements with the same amount of current, achieving the purpose of improving brightness and reducing current usage. In addition, when the number of light-emitting elements does not change, the resolution of the pixel array can be adjusted by setting the number of light-emitting elements that emit light at the same time.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

10: Pixel array

100, 200, 300, 400: display unit

Data: data voltage

EM1~EMn: Luminous signal

Ida: data current

LD1~LDn: Miniature LED

SN1~SNn: scanning signal

Sw_a: The first bypass signal

Sw_b: second bypass signal

TD: Data Switch

TE1~TEn: luminous switch

TP11~TP1x: The first bypass switch

TP21, TP22: second bypass switch

TS1~TSn, TS1a~TSna: Scan switch

Vdd: system high voltage

Vss: system low voltage

FIG. 1 is a schematic diagram of a pixel array system according to an embodiment of the invention.

FIG. 2 is a schematic circuit diagram of a display unit according to another embodiment of the invention.

FIG. 3 is a schematic circuit diagram of a display unit according to another embodiment of the invention.

FIG. 4 is a schematic circuit diagram of a display unit according to another embodiment of the invention.

Unless otherwise defined, all terms used in this article (including technical and scientific The term) has the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of related technologies and the present invention, and will not be interpreted as idealized or excessive The formal meaning, unless explicitly defined as such in this article.

It should be understood that although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and/or parts, these elements, components, regions, and/or Or part should not be restricted by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Therefore, the “first element”, “component”, “region”, “layer” or “portion” discussed below may be referred to as a second element, component, region, layer or section without departing from the teachings herein.

The terminology used here is only for the purpose of describing specific embodiments and is not limiting. As used herein, unless the content clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms, including "at least one." "Or" means "and/or". As used herein, the term "and/or" includes any and all combinations of one or more of the related listed items. It should also be understood that when used in this specification, the terms "including" and/or "including" designate the presence of the features, regions, wholes, steps, operations, elements, and/or components, but do not exclude one or more The existence or addition of other features, regions as a whole, steps, operations, elements, components, and/or combinations thereof.

FIG. 1 is a schematic diagram of a pixel array system according to an embodiment of the invention. Please refer to FIG. 1. In this embodiment, the pixel array 10 includes a plurality of display units 100. The pixel array 10 is composed of, for example, these display units 100, and each pixel row of the pixel array 10 is composed of one of the display units 100, that is, the display units 100 are arranged along the horizontal direction. However, in the embodiment of the present invention, the display unit 100 may be arranged in an array, and the embodiment of the present invention is not limited thereto.

Each display unit 100 includes a plurality of scan switches TS1~TSn, a plurality of light-emitting elements (here, a plurality of micro light-emitting diodes LD1~LDn are taken as an example), a plurality of light-emitting switches TE1~TEn, and a data switch TD, where n is A positive integer greater than 1. In another embodiment of the present invention, the plurality of light-emitting elements may be a plurality of organic light-emitting diodes. In this embodiment, the miniature light emitting diodes LD1 to LDn are serially connected in sequence and respectively have a first end (a cathode end is taken as an example here) and a second end (a cathode end is taken as an example here).

The scan switches TS1~TSn are respectively coupled between the system high voltage Vdd and the anode terminals of the corresponding miniature light emitting diodes (such as LD1~LDn). For example, the first terminal and the second terminal of the scan switch TS1 are respectively coupled to the system high voltage Vdd and the anode terminal of the micro light emitting diode LD1; the first terminal and the second terminal of the scan switch TS2 are respectively coupled to the system high voltage Vdd Same as the anode end of the miniature light-emitting diode LD2, and so on. In addition, the control terminal of each scan switch TS1~TSn receives the corresponding scan signal (such as SN1~SNn), and is controlled by the corresponding scan signal (such as SN1~SNn) to turn off or conduct. For example, the control terminal of the scan switch TS1 receives the scan signal SN1, the control terminal of the scan switch TS2 receives the scan signal SN2, and so on.

The light-emitting switches TE1 to TEn are respectively coupled between the cathode terminals of the corresponding miniature light-emitting diodes (such as LD1 to LDn) and the first end of the driving switch TD to receive the data current Ida from the driving switch TD. For example, the first end of the light-emitting switch TE1 And the second terminal are respectively coupled to the cathode terminal of the micro light emitting diode LD1 and the first terminal of the driving switch TD; the first terminal and the second terminal of the light emitting switch TE2 are respectively coupled to the cathode terminal of the micro light emitting diode LD1 With the first end of the drive switch TD, the rest can be deduced by analogy. In addition, the control terminal of each light-emitting switch TE1~TEn receives the corresponding light-emitting signal (such as EM1~EMn), and is controlled to be turned off or turned on by the corresponding light-emitting signal (such as EM1~EMn). For example, the control terminal of the light-emitting switch TE1 receives the light-emitting signal EM1, the control terminal of the light-emitting switch TE2 receives the light-emitting signal EM2, and so on.

The control terminal of the driving switch TD receives the data voltage Data, and provides a data current Ida from the first terminal of the driving switch TD according to the data voltage Data. The second end of the driving switch TD is coupled to the system low voltage Vss.

In the embodiment of the present invention, during a display period, one of the scan signals SN1~SNn is enabled, that is, one of the scan switches TS1~TSn is turned on, and the emission signals EM1~EMn are enabled. One of them is to turn on one of the light-emitting switches TE1 to TEn. For example, when the scan switch TS1 and the light-emitting switch TE1 are turned on at the same time, only the micro light-emitting diode LD1 emits light; when the scan switch TS1 and the light-emitting switch TE2 are turned on at the same time, only the micro light-emitting diodes LD1 and LD2 emit light, and the rest are based on this analogy. In other words, the position of the scanning switch (such as TS1~TSn) that is turned on at the same time and the position of the light-emitting switch (such as TE1~TEn) that are turned on at the same time determine the amount of light emitted in the miniature light-emitting diodes (such as LD1~LDn).

According to the above, the concept of series connection of light-emitting elements (such as miniature light-emitting diodes) is used, so that the data current Ida can flow the same amount of current through multiple light-emitting elements to achieve the purpose of improving the brightness and reduce the current consumption. And, with pulse The impulse emission display mode can produce different combinations of the number of light-emitting elements connected in series, which can achieve different power improvement effects; and, under the condition that the number of light-emitting elements remains unchanged, it can be adjusted by setting the number of light-emitting elements that emit light at the same time The resolution of the pixel array 10.

Furthermore, when each pixel row of the pixel array 10 is a separate display unit 100, each pixel row shares the same drive switch TD, which reduces the uniformity of the drive current of the transistor in the panel from being affected by the variation of the drive switch TD. The brightness uniformity of the pixel array 10 is improved. The driving switch TD may be located in the peripheral area of the display panel (not shown), that is, the driving switch TD does not occupy the area of the display area, and will not affect the overall display effect of the pixel array 10.

FIG. 2 is a schematic circuit diagram of a display unit according to another embodiment of the invention. 1 and 2, the display unit 200 can be used to replace the display unit 100, and the display unit 200 is substantially the same as the display unit 100, the difference lies in the scan switches TS1a~TSna, wherein the scan switches TS1a~TSna are respectively coupled It is a diode type. In this way, the number of wiring and wiring complexity in the pixel array 10 can be reduced.

FIG. 3 is a schematic circuit diagram of a display unit according to another embodiment of the invention. 1 and 3, the display unit 300 can be used to replace the display unit 100, and the display unit 300 is substantially the same as the display unit 100, the difference is that the display unit 300 further includes first bypass switches TP11~TP1x, where x It is a positive integer less than n, and can be close to or equal to n/2.

In this embodiment, odd-numbered micro-light-emitting diodes LD1, LD3,..., LDn-1 among micro-light-emitting diodes LD1~LDn and even-numbered micro-light-emitting diodes LD2 LD4,..., LDn can be miniature light-emitting diodes with different light-emitting characteristics, the light-emitting characteristics can be light-emitting color, light-emitting intensity, light-emitting light field, etc., where the light field can be understood as different light with different viewing angles strength. Furthermore, the first bypass switches TP11~TP1x are respectively connected in parallel with even-numbered miniature light-emitting diodes LD2, LD4, ..., LDn (corresponding to the first miniature light-emitting diodes), and the first bypass switches TP11~TP1x The control ends of the two receive the first bypass signal Sw_a to be turned on or off under the control of the first bypass signal Sw_a, that is, the even-numbered micro light emitting diodes LD2, LD4,..., LDn that are not adjacent to each other are controlled The first bypass signal Sw_a is in an active state or an inactive state.

For example, suppose that the odd-numbered micro light-emitting diodes LD1, LD3, ..., LDn-1 have narrow viewing angle effects, and the even-numbered micro light-emitting diodes LD2, LD4, ..., LDn have wide viewing angle effects. When the first bypass signal Sw_a turns on the first bypass switches TP11~TP1x, the display unit 300 only has a narrow viewing angle effect to improve visual confidentiality; when the first bypass signal Sw_a turns off the first bypass switch TP11 When ~TP1x, the display unit 300 has a wide viewing angle effect to improve visual visibility.

In this embodiment, the micro light emitting diodes LD1~LDn are divided into odd micro light emitting diodes LD1, LD3,..., LDn-1 (corresponding to the second micro light emitting diode) and even micro light emitting diodes. Polar bodies LD2, LD4,..., LDn (corresponding to the first miniature light-emitting diode), that is, the first miniature light-emitting diode with the first light-emitting characteristic is set directly with the second miniature light-emitting diode with the second light-emitting characteristic At least one of the light-emitting diodes is directly adjacent. In other embodiments, a micro light emitting diode with other light emitting characteristics can be inserted between the first micro light emitting diode and the second micro light emitting diode. Depending on the circuit design, the embodiment of the present invention is not limited thereto.

In other words, in the above-mentioned embodiment, the micro light emitting diodes LD1~LDn are respectively the first group and the second group, and the synchronously controlled bypass switch determines (controls) which of the first group and the second group One of the active states. However, in other embodiments, the micro light emitting diodes LD1 ~ LDn can be divided into multiple groups, and multiple synchronously controlled bypass switch groups can be used to control the corresponding micro light emitting diode groups. Action status.

FIG. 4 is a schematic circuit diagram of a display unit according to another embodiment of the invention. 3 and 4, the display unit 400 can be used to replace the display unit 100, and the display unit 400 is substantially the same as the display unit 300, the difference is that the display unit 400 further includes a second bypass switch (such as TP21, TP22) , Where the number of second bypass switches can approach or be equal to n/2. The second bypass switch (such as TP21, TP22) is connected in parallel with odd-numbered miniature light-emitting diodes LD1, LD3,..., LDn-1, and the control terminal of the second bypass switch (such as TP21, TP22) receives The second bypass signal Sw_b is turned on or off under the control of the first bypass signal Sw_b, that is, odd-numbered micro light-emitting diodes LD1, LD3,..., LDn-1 that are not adjacent to each other are controlled by the second The bypass signal Sw_b is in an active state or an inactive state. Wherein, the first bypass signal Sw_a is different from the second bypass signal Sw_b, and at least one of the first bypass signal Sw_a and the second bypass signal Sw_b is disabled, that is, the odd-numbered miniature light-emitting diodes LD1, LD3 ,..., LDn-1 and at least one of the even-numbered miniature light-emitting diodes LD2, LD4,..., LDn are in an active state.

In summary, the pixel array of the embodiment of the present invention uses light-emitting elements (example Such as the concept of miniature light-emitting diodes) in series, so that the data current can flow through the same amount of current through multiple light-emitting elements, to achieve the purpose of improving the brightness, and can reduce the current consumption. In addition, when the number of light-emitting elements does not change, the resolution of the pixel array can be adjusted by setting the number of light-emitting elements that emit light at the same time.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be determined by the scope of the attached patent application.

10: Pixel array

100: display unit

Data: data voltage

EM1~EMn: Luminous signal

Ida: data current

LD1~LDn: Miniature LED

SN1~SNn: scanning signal

TD: Data Switch

TE1~TEn: luminous switch

TS1~TSn: Scan switch

Vdd: system high voltage

Vss: system low voltage

Claims (12)

A pixel array, including: Multiple display units, including: A plurality of light-emitting elements are serially connected in sequence and each has a first end and a second end; A plurality of scan switches are respectively coupled to the first end of the corresponding light-emitting element among the light-emitting elements; A data switch that receives a data voltage to provide a data current according to the data voltage; and A plurality of light-emitting switches are respectively coupled between the second end of the corresponding light-emitting element among the light-emitting elements and the drive switch for receiving the data current, Among them, the turned-on scan switch and the turned-on light-emitting switch determine the amount of light emitted in the light-emitting elements. In the pixel array described in the first item of the patent application, in a display period, one of the scan switches is turned on, and one of the light-emitting switches is turned on. In the pixel array described in claim 1, wherein the scan switches are respectively coupled between a system high voltage and the first end of the corresponding light-emitting element among the light-emitting elements. The pixel array described in item 1 of the scope of patent application further includes: A plurality of first bypass switches are respectively connected in parallel with the plurality of first light-emitting elements of the light-emitting elements, and jointly receive a first bypass signal to be turned on or off under the control of the first bypass signal, wherein the The first light emitting elements are not adjacent to each other. The pixel array described in item 4 of the scope of patent application further includes: A plurality of second bypass switches are respectively connected in parallel with the plurality of second light-emitting elements of the light-emitting elements, and jointly receive a second bypass signal to be turned on or off under the control of the second bypass signal, wherein The second light-emitting element is different from the first light-emitting elements and is not adjacent to each other. The pixel array described in claim 4, wherein the first bypass signal is different from the second bypass signal. According to the pixel array described in claim 6, wherein at least one of the first bypass signal and the second bypass signal is disabled. The pixel array described in claim 4, wherein the first light-emitting elements are different from the second light-emitting elements. As described in the first item of the scope of patent application, each of the scan switches receives a corresponding scan signal to be turned off or turned on under the control of the corresponding scan signal, and each of the light-emitting switches receives a corresponding light-emitting signal , To be controlled by the corresponding light-emitting signal to turn off or turn on. The pixel array described in item 1 of the scope of patent application, wherein each pixel row of the pixel array is formed by one of the display units. In the pixel array described in item 1 of the scope of patent application, the scan switches are respectively coupled in a diode type. According to the pixel array described in claim 1, wherein the light-emitting element includes one of a micro light-emitting diode and an organic light-emitting diode.

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